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Heated Grip--left side fail

Hey all, my 98 R1100r left side heated grip has failed. I've got proper voltages at the rocker switch (hi-11.5v/low 9.5v) and at the wires to the element in the grip. Since buying this bike from the PO, I've had to clean/lubricate the switch internally, and only just realized that it was 3-way, as it was physically stuck from corrosion.

I've also tested for continuity between the leads at the grip, which was good.

So if I've got voltage and continuity through the circuit, where is the failure? I guess the one last thing to do is check the connection at the main wiring harness under the tank, correct?

Took the tank off, cleaned the connectors, checked for continuity and voltage and all good. Must be the grip element!

Well, go to the connector where the left grip plugs into the harness again. Re-verify voltage at that connection to a known good ground. Then use a continuity tester to verify the ground wire on the harness side is a good ground return path.

Then use an Ohm meter to read the resistance from one pin on the grip side through the grip to the other pin on the grip side.

These three tests tell what is going on.

1. 12v at hot pin on harness side: yes or no.
2. Ground path on harness side: yes or no.
3. Continuity through the grip with high resistance: yes, or reading open.

If one fails backtrack through the harness.
If two fails then backtrack till you find where the ground is lost.
If three fails the grip is shot.

My guess is #2.

Paul Glaves - "Big Bend", Texas U.S.A
"The greatest challenge to any thinker is stating the problem in a way that will allow a solution." - Bertrand Russellhttp://web.bigbend.net/~glaves/

Then, do you mean measure resistance between both pins at the grip end, where they connect to the heater element wires in the grip? I've already done that and gotten high resistance.

Originally Posted by PGlaves

Well, go to the connector where the left grip plugs into the harness again. Re-verify voltage at that connection to a known good ground. Then use a continuity tester to verify the ground wire on the harness side is a good ground return path.

Then use an Ohm meter to read the resistance from one pin on the grip side through the grip to the other pin on the grip side.

These three tests tell what is going on.

1. 12v at hot pin on harness side: yes or no.
2. Ground path on harness side: yes or no.
3. Continuity through the grip with high resistance: yes, or reading open.

If one fails backtrack through the harness.
If two fails then backtrack till you find where the ground is lost.
If three fails the grip is shot.

Then, do you mean measure resistance between both pins at the grip end, where they connect to the heater element wires in the grip? I've already done that and gotten high resistance.

Second question first. If you are getting a high ohm reading through the grip - both pins at the grip side of the connector - that grip is testing good. Do the test at the connector so you are testing the wire to the grip and the wire through the grip.

Now for the ground return path. Again, use the Ohm meter. Identify the ground pin on the harness side of the connector. It will be the one that doesn't have 12v to it, and probably is a brown wire. Measure resistance from that pin to either a good ground on the chassis or to the battery ground (negative) terminal. You should get a reading of just a few Ohms. If the reading is open you have lost the ground completely from a very bad connection or a broken wire. If you get a reading of very high resistance then that signals a dirty or loose connection.

Paul Glaves - "Big Bend", Texas U.S.A
"The greatest challenge to any thinker is stating the problem in a way that will allow a solution." - Bertrand Russellhttp://web.bigbend.net/~glaves/

Second question first. If you are getting a high ohm reading through the grip - both pins at the grip side of the connector - that grip is testing good. Do the test at the connector so you are testing the wire to the grip and the wire through the grip.

Now for the ground return path. Again, use the Ohm meter. Identify the ground pin on the harness side of the connector. It will be the one that doesn't have 12v to it, and probably is a brown wire. Measure resistance from that pin to either a good ground on the chassis or to the battery ground (negative) terminal. You should get a reading of just a few Ohms. If the reading is open you have lost the ground completely from a very bad connection or a broken wire. If you get a reading of very high resistance then that signals a dirty or loose connection.

Ok, still a little confused, thank you for your patience...If i have it right, you are saying check for resistance where the grip leads are plugged into the harness connector under the tank, since I've checked the leads at the handlebar? Or are you saying put one probe on the grip/handlebar lead, and one on the grip side at the connector to test resistance all the way back to the connector through the entire grip circuit?

Measuring between C and frame ground / battery negative, you should have little to no resistance.
(The same should be true between G and frame ground / battery negative - right grip heater)

Measuring between A and B should give you high resistance. (The grip harnesses should be unplugged for this.)
(The same should be true between E and F and the values should be similar - right grip heater)

With the switch on high, measuring between M and frame ground / battery negative gave you 11.5V.
(The grip harnesses should be unplugged for this.)
(The same should be true between D and frame ground / battery negative)
(The same should be true between D and C)
(The same should be true between H and frame ground / battery negative - right grip heater)
(The same should be true between H and G - right grip heater)

With the switch on low, measuring between N and frame ground / battery negative gave you 9.5V.
(The grip harnesses should be unplugged for this.)
(The same should be true between D and frame ground / battery negative)
(The same should be true between D and C)
(The same should be true between H and frame ground / battery negative - right grip heater)
(The same should be true between H and G - right grip heater)

FIXED!!! Woo hoo!

Hey guys, thanks for your help. Fresh battery in the multimeter was the first step. Then I got a no-continuity reading on the grip side of the connector for the left side. With the probes attached, i found a poor connection under the grip, which I pulled back and after removing the brown tape, found a broken element wire! I stripped out a bare piece of wire and spliced/braided it on, taped it all up nice and tight and VOILA! Warm hand!!

In the meantime, I also got to inspect, re-tape and re-ziptie the wiring harness all the way along, as well as clean all connectors.